#define _CRT_SECURE_NO_WARNINGS 1
#include "Date.h"

void Date::Print()
{
	cout << _year << "-" << _month << "-" << _day  << endl;
}

int Date::GetMonthDay(int year, int month)
{
	assert(year > 1 && month < 13 && month >0);
	int arr[] = { 0, 31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30,31 };
	if (month == 2 && ((year % 4 == 0 && year % 100 != 0) || year % 400 == 0))
		return 29;
	else
		return arr[month];
}

Date::Date(int year, int month, int day)
{
	_year = year;
	_month = month;
	_day = day;
}

Date::Date(const Date& d)
{
	_year = d._year;
	_month = d._month;
	_day = d._day;
}

Date& Date::operator=(const Date& d)
{
	_year = d._year;
	_month = d._month;
	_day = d._day;
	return *this;
}

Date::~Date()
{
	_year = 0;
	_month = 0;
	_day = 0;
}

Date& Date::operator+=(int day)
{
	if (day < 0)
	{
		return *this -= (-day);
	}
	_day += day;
	while (_day > Date::GetMonthDay(_year,_month))
	{
		_day -= GetMonthDay(_year, _month);
		_month++;
		if (_month == 12)
		{
			_year++;
			_month = 1;
		}
	}
	return *this;
}

Date Date::operator+(int day)
{
	Date tmp(*this);
	tmp += day;
	return tmp;
}

Date& Date::operator-=(int day)
{
	if (day < 0)
	{
		return *this += (-day);
	}

	_day -= day;
	while (_day <=0)
	{
		_month--;
		if (_month == 0)
		{
			_year--;
			_month = 12;
		}
		_day += Date::GetMonthDay(_year, _month);
	}
	return *this;
}

Date Date::operator-(int day)
{
	Date tmp(*this);
	tmp -= day;
	return tmp;
}

Date& Date::operator++()
{
	*this += 1;
	return *this;
}

Date Date::operator++(int)
{
	Date tmp(*this);
	tmp += 1;
	return tmp;
}

Date& Date::operator--()
{
	*this -= 1;
	return *this;
}

Date Date::operator--(int)
{
	Date tmp(*this);
	tmp -= 1;
	return tmp;
}

bool Date::operator>(const Date& d)
{
	{
		if (_year > d._year)
		{
			return true;
		}
		else if (_year == d._year && _month > d._month)
		{
			return true;
		}
		else if (_year == d._year && _month == d._month && _day > d._day)
		{
			return true;
		}
		return false;
	}
}

bool Date::operator==(const Date& d)
{
	return (_year == d._year && _month == d._month && _day == d._day);
}

bool Date::operator >= (const Date& d)
{
	return *this > d || *this == d;
}

bool Date::operator < (const Date& d)
{
	{
		if (_year < d._year)
		{
			return true;
		}
		else if (_year == d._year && _month < d._month)
		{
			return true;
		}
		else if (_year == d._year && _month == d._month && _day < d._day)
		{
			return true;
		}
		return false;
	}
}

bool Date::operator <= (const Date& d)
{
	return *this < d || *this == d;
}

bool Date::operator != (const Date& d)
{
	return !(*this == d);
}

int Date::operator-(const Date& d)
{
	int flag = 1;
	Date max = *this;
	Date min = d;

	if (*this < min)
	{
		max = min;
		min = *this;
		flag = -1;
	}

	int n = 0;
	while (max != min)
	{
		n++;
		++min;
	}
	return n * flag;
}